For this case, what we must do is equal the function to zero: b ^ 2 - 75 = 0 From here, we clear the value of b. We have then: b = + / - root (75) We rewrite: b = + / - root (3 * 25) b = + / - 5 * root (3) So, the roots are: b1 = 5 * root (3) b2 = -5 * root (3) Answer: The roots of the quadratic function are: b1 = 5 * root (3) b2 = -5 * root (3)